Generally, an USB memory package comprises: a substrate with an USB plug formed on one end thereof; a flash memory electrically connected with the substrate of one end of the USB plug; a controller electrically connected with the substrate of the other end of the USB plug and controlling the flash memory and so on; a passive element electrically connected with the substrate of the other end of the USB plug; and a case coupled with the substrate and protecting the flash memory, the controller and the passive element.
The USB memory package, as is well known, is manufactured and sold in various forms. However, the USB plug commonly assumes the form of being protruded outwardly from the substrate or the case by a certain length. Of course, the USB plug assumes the form of being coupled with an USB receptacle mounted on a computer and so on, and any of the flash memory, the controller or the passive element cannot be mounted on the region on which the USB plug is formed.
Accordingly, the USB plug acts as an obstacle to reduce the size and the weight of a conventional USB memory package. That is, due to the USB plug, it is difficult to reduce the size and the weight of the USB memory package.
Furthermore, according to the conventional USB memory package, in case of the flash memory, a semiconductor package preformed in the form of TSOP (Thin Small Outline Package) or FBGA (Fine Ball Grid Array) is mounted on the substrate, and in case of the controller, a semiconductor package preformed in the form of QFP (Quad Flat Package) or FBGA is mounted on the substrate. Accordingly, since the memory capacity of the conventional USB memory package is already fixed in the form of TSOP or FBGA (In other words, it is not possible to expand the memory capacity.), it is difficult to expand the memory capacity. Moreover, since the already finished semiconductor package is mounted on the substrate, a problem of high manufacturing cost is arisen.
Furthermore, according to the conventional USB memory package, there is a problem that an LED element indicating the operating state is mounted on the substrate and a case should be formed so as to expose the LED element to the outside of the case. Of course, there is also a problem that moisture or a foreign substance can be easily penetrated into a gap between the LED element and the case.
Furthermore, according to the conventional USB memory package, there is a problem that since the USB plug is formed on only one end of the USB memory package, the user has to exactly couple the USB receptacle with the corresponding side of the USB memory package.